1. Field of the Invention
Aspects of the present invention relate generally to an apparatus and a method for recognizing an error of a toner sensor for a developing device, and more particularly to an apparatus and a method for recognizing an error of a toner sensor for a developing device that compares the output value and the set value of a toner sensor accommodated in a main body of the developing device with each other to correctly recognize the error.
2. Description of the Related Art
In general, in a copier, a printer, a multifunction printer, and a facsimile, in order to record an image on a recording medium using a developer such as a toner, an image forming apparatus of an electro-photography method is provided. Such an image forming apparatus is divided into a mono image forming apparatus and a color image forming apparatus. A mono image forming apparatus forms a single color image. A color image forming apparatus overlaps yellow (Y), magenta (M), cyan (C), and black (K) colors with each other to realize a desired image. Therefore, the mono image forming apparatus requires a developing cartridge of one color and the color image forming apparatus requires four developing cartridges that store toners of four colors, respectively.
On the other hand, the developing cartridge is divided into a monolithic structure in which a toner is stored in the developing cartridge and a separate structure in which a toner container in which a toner is stored is separate from the main body of a developing device. In the case of the monolithic structure, the developing cartridge is exchanged with a new developing cartridge after the toner is used. However, in the case of the separate structure, after the toner is used, the main body of the developing device is left as it is and the empty toner container is exchanged with a new toner container. Therefore, the separate structure is more economical.
In the case of the separate structure, since the toner of the toner container is supplied to the main body of the developer, it is necessary to determine whether the toner exists in the main body of the developing device as well as in the toner container. When a sensor that senses the toner of the main body of the developing device is provided, the reliability of the output value of the sensor must be secured.
When the reliability of the output value of the sensor is not secured, the amount of the toner filled in the main body of the developing device may be erroneously determined. When it is determined that the toner is insufficient by the sensor value measured using the sensor although the main body of the developing device is filled with the toner, the toner is unnecessarily supplied. As a result, the main body of the developing device may explode. Also, when it is determined that the toner is sufficient by the sensor value although the toner in the main body of the developing device is exhausted so that the toner must be supplied, since the toner is not supplied from the toner container to the main body of the developing device, printing quality deteriorates.